This invention relates to a suction nozzle for use on a spin-draw-winding machine. More particularly, the invention is for an improved suction nozzle capable of picking up and aspirating away a high-speed threadline. Machines have been described in which the functions of spinning, drawing and winding are all combined in one machine and which operate at very high threadline speeds. In addition to high thread-line speeds, multiple threadlines are usually spun and processed together over a series of rolls on a single machine. From two to eight or more threadlines, constituting a running warp, may be simultaneously processed on one spin-draw machine roll system. Spacing between the threadlines is very close, particularly when the warp is helically wrapped on the processing rolls to increase residence time. Because of the close proximity of threadlines in the running warp, it is not uncommon for a single broken threadline to disrupt adjacent threadlines and in many instances to cause a complete breakdown of the entire warp. At modern high-speed processing rates and close threadline spacing this occurs in a fraction of a second. As a consequence, maintenance of multiple threadline operation in a continuous mode over an extended production run requires constant vigilance by a large number of skilled personnel.
Suction nozzles have been used to aspirate away broken threadlines and thus protect the running warps of textile spinning machines. While these nozzles have performed satisfactorily at low yarn speeds, they do not have the pulling power to rapidly and reliably capture, remove and hold a broken threadline at the high yarn speeds now in use. It is the object of this invention to provide an improved suction nozzle which is capable of picking up and aspirating away high-speed threadlines. The improved nozzle protects a running warp against interference from broken threadlines and prevents yarn processing roll wraps.